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Reducing non-radiative recombination and addressing band alignment mismatches at interfaces remain major challenges in achieving high-performance wide-bandgap perovskite solar cells. This study proposes the self-organization of a thin two-dimensional (2D) perovskite BA2PbBr4 layer beneath a wide-bandgap three-dimensional (3D) perovskite Cs0.17FA0.83Pb(I0.6Br0.4)3, forming a 2D/3D bilayer structure on a tin oxide (SnO2) layer. This process is driven by interactions between the oxygen vacancies on the SnO2 surface and hydrogen atoms of the n-butylammonium cation, aiding the self-assembly of the BA2PbBr4 2D layer. The 2D perovskite acts as a tunneling layer between SnO2 and the 3D perovskite, neutralizing the energy level mismatch and reducing non-radiative recombination. This results in high power conversion efficiencies of 21.54% and 19.16% for wide-bandgap perovskite solar cells with bandgaps of 1.7 and 1.8 eV, with open-circuit voltages over 1.3 V under 1-Sun illumination. Furthermore, an impressive efficiency of over 43% is achieved under indoor conditions, specifically under 200 lux white light-emitting diode light, yielding an output voltage exceeding 1 V. The device also demonstrates enhanced stability, lasting up to 1,200 hours.
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Scanning probe microscopy (SPM) has enabled significant new insights into the nanoscale and microscale properties of solar cell materials and underlying working principles of photovoltaic and optoelectronic technology. Various SPM modes, including atomic force microscopy, Kelvin probe force microscopy, conductive atomic force microscopy, piezoresponse force microscopy, and scanning near-field optical microscopy, can be used for the investigation of electrical, optical and chemical properties of associated functional materials. A large body of work has improved the understanding of solar cell device processing and synthesis in close synergy with SPM investigations in recent years. This review provides an overview of SPM measurement capabilities and attainable insight with a focus on recently widely investigated halide perovskite materials.
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A novel Gram-negative, white-pigmented, and auxin-producing strain, 20NA77.5T, was isolated from fresh water during cyanobacterial bloom period. Pairwise comparison of the 16S rRNA gene sequences showed that strain 20NA77.5T belonged to the genus Undibacterium and exhibited the highest sequence similarity to the type strains of Undibacterium danionis (98.00%), Undibacterium baiyunense (97.93%), Undibacterium macrobrachii (97.92%), and Undibacterium fentianense (97.71%). The average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values between strain 20NA77.5T and its related type strains were below 79.93 and 23.80%, respectively. The predominant fatty acids (> 10% of the total fatty acids) were C16:0 and summed feature 3 (C16:1ω7c and/or C16:1ω6c). The genomic DNA G + C content of strain 20NA77.5T was found to be 48.61%. Based on the phylogenetic distinctness, chemotaxonomic features, and phenotypic features, strain 20NA77.5T is considered to represent a novel species of the genus Undibacterium, for which the name Undibacterium cyanobacteriorum sp. nov is proposed. The type strain is 20NA77.5T (= KCTC 8005T = LMG 33136T).
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Técnicas de Tipagem Bacteriana , Composição de Bases , Cianobactérias , DNA Bacteriano , Ácidos Graxos , Água Doce , Ácidos Indolacéticos , Filogenia , RNA Ribossômico 16S , RNA Ribossômico 16S/genética , DNA Bacteriano/genética , Água Doce/microbiologia , Ácidos Indolacéticos/metabolismo , Ácidos Graxos/análise , Cianobactérias/genética , Cianobactérias/classificação , Cianobactérias/isolamento & purificação , Cianobactérias/metabolismo , Hibridização de Ácido Nucleico , Análise de Sequência de DNA , Microbiologia da ÁguaRESUMO
Fusarium head blight (FHB) is a destructive disease caused by several species of Fusarium, such as Fusarium graminearum and F. asiaticum. FHB affects cereal crops, including wheat, barley, and rice, worldwide. Fusarium-infected kernels not only cause reduced yields but also cause quality loss by producing mycotoxins, such as trichothecenes and zearalenone, which are toxic to animals and humans. For decades, chemical fungicides have been used to control FHB because of their convenience and high control efficacy. However, the prolonged use of chemical fungicides has caused adverse effects, including the emergence of drug resistance to pathogens and environmental pollution. Biological control is considered one of the most promising alternatives to chemicals and can be used for integrated management of FHB due to the rare possibility of environment pollution and reduced health risks. In this study, Bacillus velezensis JCK-7158 isolated from rice was selected as an ecofriendly alternative to chemical fungicides for the management of FHB. JCK-7158 produced the extracellular enzymes protease, chitinase, gelatinase, and cellulase; the plant growth hormone indole-3-acetic acid; and the 2,3-butanediol precursor acetoin. Moreover, JCK-7158 exhibited broad antagonistic activity against various phytopathogenic fungi and produced iturin A, surfactin, and volatile substances as active antifungal compounds. It also enhanced the expression of PR1, a known induced resistance marker gene, in transgenic Arabidopsis plants expressing ß-glucuronidase (GUS) fused with the PR1 promoter. Under greenhouse conditions, treatments with the culture broth and suspension concentrate formulation of JCK-7158 at a 1,000-fold dilution inhibited the development of FHB by 50 and 66%, respectively. In a field experiment, treatment with the suspension concentrate formulation of JCK-7158 at a 1,000-fold dilution effectively controlled the development of FHB with a control value of 55% and reduced the production of the mycotoxin nivalenol by 40%. Interestingly, treatment with JCK-7158 enhanced the expression of plant defense-related genes in salicylic acid, jasmonic acid, ethylene, and reactive oxygen species (ROS) signaling pathways before and after FHB pathogen inoculation. Taken together, our findings support that JCK-7158 has the potential to serve as a new biocontrol agent for the management of FHB.
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BACKGROUND: Allergies often present challenges in managing itch and the effects of histamine. Cooling agents that act via transient receptor potential melastatin 8 (TRPM8) agonism have shown potential in itch management. However, animal studies on itch have limitations, as animals cannot communicate subjective events and their fur-coated skin differs from that of humans. Human studies offer more direct and reliable information. OBJECTIVES: To investigate the effects of a specific TRPM8 agonist gel (cryosim-1) on itch induced by various pruritogens in human skin. METHODS: Calcium imaging experiments determined the binding of cryosim-1 and histamine to their respective receptors. Thirty healthy volunteers underwent skin prick tests with pruritogens and a control vehicle. Itch and pain intensity were measured using a numerical rating scale (NRS) across 10â min. Participants were randomly assigned to pretreatments with vehicle or TRPM8 agonist gel. Tests were repeated at a later date, and skin moisture, transepidermal water loss and mechanical sensitivity were measured. RESULTS: The in vitro study confirmed that histamine is not a TRPM8 agonist and cryosim-1 does not act as an agonist or antagonist on the human histamine 1 receptor. The TRPM8 agonist gel significantly reduced the itch intensity for all pruritogens compared with the vehicle-only gel. It also reduced itch NRS and the integrated itch score. Mechanical sensitivity was also reduced. CONCLUSIONS: The specific TRPM8 agonist gel effectively suppressed human skin itch induced by various pruritogens. These versatile actions suggest that cooling agents may be promising treatments for multiple forms of itch stimuli.
Managing itching and the effects of histamine can be difficult for people with allergies. Cooling the skin or applying menthol provides some relief from itch, but the way they work is not fully understood. Cooling agents interact with a protein called TRPM8 (also known as the 'cold and menthol receptor') and have shown potential for the management of itch. However, much of the research has been done on animals and has limitations when compared with human studies. Antihistamine medications can help with histamine-induced itching, but they may not work for other causes of itch. This study investigated the effects of a specific TRPM8 agonist (a chemical that activates a receptor to produce a biologic response) gel called cryosim-1 on itch in human skin. To do this, we conducted tests on 30 healthy people using five different substances that cause itching. Participants rated the itch intensity and pain using a scale and we measured various aspects of their skin. The results showed that all substances caused significant itching compared to a control substance, but itchiness gradually decreased over time. Histamine and compound 48/80 also caused pain. However, when participants applied the TRPM8 activator gel before exposure, they experienced less itching and lower itch intensity versus the gel without the activator. There were no significant differences in pain between the TRPM8 activator and the gel without it. In summary, our findings showed that activating TRPM8 receptors with a specific substance effectively relieved itching caused by various irritants on human skin. This suggests its potential as a treatment for itch-related conditions. Further research is needed to understand its mechanisms better and evaluate its effectiveness in real-life situations.
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Histamina , Prurido , Canais de Cátion TRPM , Humanos , Prurido/tratamento farmacológico , Prurido/induzido quimicamente , Canais de Cátion TRPM/agonistas , Canais de Cátion TRPM/antagonistas & inibidores , Adulto , Masculino , Histamina/administração & dosagem , Histamina/efeitos adversos , Feminino , Adulto Jovem , Géis , Pessoa de Meia-Idade , Antipruriginosos/administração & dosagem , Antipruriginosos/farmacologia , Antipruriginosos/efeitos adversos , Método Duplo-Cego , Administração CutâneaRESUMO
The conservation of the endangered Korean fir, Abies koreana, is of critical ecological importance. In our previous study, a yeast-like fungus identified as Aureobasidium pullulans AK10, was isolated and shown to enhance drought tolerance in A. koreana seedlings. In this study, the effectiveness of Au. pullulans AK10 treatment in enhancing drought tolerance in A. koreana was confirmed. Furthermore, using transcriptome analysis, we compared A. koreana seedlings treated with Au. pullulans AK10 to untreated controls under drought conditions to elucidate the molecular responses involved in increased drought tolerance. Our findings revealed a predominance of downregulated genes in the treated seedlings, suggesting a strategic reallocation of resources to enhance stress defense. Further exploration of enriched Kyoto Encyclopedia of Genes and Genomes pathways and protein-protein interaction networks revealed significant alterations in functional systems known to fortify drought tolerance, including the terpenoid backbone biosynthesis, calcium signaling pathway, pyruvate metabolism, brassinosteroid biosynthesis, and, crucially, flavonoid biosynthesis, renowned for enhancing plant drought resistance. These findings deepen our comprehension of how AK10 biostimulation enhances the resilience of A. koreana to drought stress, marking a substantial advancement in the effort to conserve this endangered tree species through environmentally sustainable treatment.
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Apple fire blight, caused by the bacterium Erwinia amylovora, is a devastating disease of apple and pear trees. Biological control methods have attracted much attention from researchers to manage plant diseases as they are eco-friendly and viable alternatives to synthetic pesticides. Herein, we isolated Streptomyces sp. JCK-8055 from the root of pepper and investigated its mechanisms of action against E. amylovora. Streptomyces sp. JCK-8055 produced aureothricin and thiolutin, which antagonistically affect E. amylovora. JCK-8055 and its two active metabolites have a broad-spectrum in vitro activity against various phytopathogenic bacteria and fungi. They also effectively suppressed tomato bacterial wilt and apple fire blight in in vivo experiments. Interestingly, JCK-8055 colonizes roots as a tomato seed coating and induces apple leaf shedding at the abscission zone, ultimately halting the growth of pathogenic bacteria. Additionally, JCK-8055 can produce the plant growth regulation hormone indole-3-acetic acid (IAA) and hydrolytic enzymes, including protease, gelatinase, and cellulase. JCK-8055 treatment also triggered the expression of salicylate (SA) and jasmonate (JA) signaling pathway marker genes, such as PR1, PR2, and PR3. Overall, our findings demonstrate that Streptomyces sp. JCK-8055 can control a wide range of plant diseases, particularly apple fire blight, through a combination of mechanisms such as antibiosis and induced resistance, highlighting its excellent potential as a biocontrol agent. KEY POINTS: ⢠JCK-8055 produces the systemic antimicrobial metabolites, aureothricin, and thiolutin. ⢠JCK-8055 treatment upregulates PR gene expression in apple plants against E. amylovora. ⢠JCK-8055 controls plant diseases with antibiotics and induced resistance.